Remove bottom and find the diode matrix (near big chip)
Open RX 0.030-74.8Mhz (REMOVE D416)
Open TX 0.1-74.8Mhz (REMOVE D422) (D419 is and must be in)
** Only Open TX 60Mtr 5.255-5.405Mhz (REMOVE D405)
73 Marcus PA2DB
Well, I made the mods (both for wide open and for 60 m band and it worked perfectly on an european version with the first firmware.
After flashing the updates, the mod remained there...
A proper modification, at least how I made it, can be watched on the video below.
Check at min 21:00 to see the diode matrix after the mod!
Some words of "wisdom" to read BEFORE you proceed to the mod:
Just like any other mods, beware that you do it on your risk and you loose the warranty!
1. Check the radio to be disconnected from power supply
2. Please, use ESD discharge measures! No kidding, use ESD countermeasures both for your body and for the soldering station!
3. Use a lot of soldering flux! The diodes are very sensitive to high temperature and the solder Flux (I use GEL type) help in reducing the temperature for the areas not touched by the soldering station's tip.
4. Use 60/40 soldering alloy to reduce the melting point for the ROHS solders!
5. Use unsolder braid to clean the PCB pads!
6. Use a good soldering station!
7. Use good tweezers.
8. Use good magnifing glasses AND/OR microscope. The diodes are very very small.
I had some e-mails form a fellow ham who removed the D413 from error and the radio is not working on 6m band! He put the diode back but the radio remains without 6 m band.
I do not know if he fried the original diode but AFAIK, the diode matrix established the country version.
I suggest to put the diodes just as above and do a reflash.
I just test to see if a downgrade to 1.12 (now I have 1.13) is possible and it is!
Just for reference: